The present invention relates generally to welding implements and, more particularly, to cooling systems for welding implements.
Welding is a fabrication process for joining two or more materials together by heating the materials and allowing them to flow together. In one type of welding, gas tungsten arc welding (GTAW), an electrical current is directed through a non-consumable tungsten electrode housed in a welding implement, such as a torch. The current arcs from the electrode to a work piece, which is placed within the welding circuit. The heat generated by the arc can cause the work piece to melt and form a weld. In other types of welding, such as gas metal arc welding (GMAW), a consumable filler wire is fed through a welding implement (i.e., a gun) as an electrical current heats the wire and the work piece. The filler wire melts and is deposited on the work piece, forming the weld.
During the welding process, large amounts of heat are generated near the arc. This heat is transferred not only to the work piece to form the weld, but also to the components of the welding implement. In particular, the torch head can experience an extreme rise in temperature. Additionally, the current-carrying components of the welding implement can heat due to resistance heating. This rise in temperature can detrimentally affect the longevity and operability of the welding implement.
Increasingly, the market is demanding welding implements that are smaller, for more maneuverability, but that can also carry more current, for increased weld depth penetration. These compact, high-powered welding devices require improved techniques of heat dissipation. Many attempts have been made to improve the transfer of heat out of welding implements, especially during extended use.
Heat regulation in traditional welding implements has been addressed in a variety of ways with marginal results. For example, in TIG welding applications, the welding implement (i.e., torch) typically includes copper or brass current-carrying components that are designed to conduct heat away from the head of the torch toward the base of the torch body. Lower-temperature shielding gas is then passed over the torch body in an attempt to remove the heat from the torch via forced convection. To improve heat transfer, the component size has been increased to provide more heat carrying capacity. However, this approach results in a larger torch with less maneuverability.
Another technique incorporates a torch handle or body having ribs or fins to help increase the rate of heat dissipation to the surrounding environment. Again, however, this approach leads to a larger torch making it less desirable for certain applications.
Yet another cumbersome technique involves liquid-cooled welding implements. A liquid coolant is circulated via pump within the welding component where it comes into contact with and cools higher-temperature components. Distinct coolant passages are designed into the welding implement to maximize the heat removal. This technique has the obvious drawback of requiring an additional liquid coolant circulation system in addition to a larger welding-type gun to accommodate the cooling passageways.
Therefore, it would be desirable to have a compact, self-contained welding implement capable of autonomously regulating the temperature of the welding implement during use.